sous-vide

Sous vide cookers aren’t anything new, but [Phil] wanted to build the first sous vide using the osPID, an open source PID controller just released in the last month.

The build uses the osPID Open Source PID controller we saw last week that comes with inputs for a thermocouple and pair of relays capable of switching a hot plate or immersion heater. The osPID is based on the Arduino and was created by [Brett Beauregard], author of the Arduino PID library.

Getting to the meat and potatoes of the build, [Phil] connected a 300 Watt immersion heater to the osPID and put the heater in a bowl of water. A delicious looking cut of beef tenderloin was shoved into a ziplock bag and suspended in the bowl of warm water for a few hours. With the heater and thermocouple attached to the osPID, the temperature was set at 130° F and the entire device was left alone for a few hours. Looking at [Phil]’s recipe for tenderloin with lemon parsley butter whets our taste buds, so we’ll hope [Phil]’s dinner came out just fine.

It’s not that we haven’t seen inexpensive Sous Vide builds. It’s just that we enjoy the fact that [Kelvin’s] Sous Vide machine gives new life to unused things. The cooking vessel is a crock pot which he acquired for just $3. He housed it in a large Styrofoam box which he got for free through his local freecycle program. The circulation pump is a $0.99 fish tank part that pushes about ten gallons per hour.

He even hunted around to find the best prices on the control circuitry. The PID controller is obviously the most important part, as it will regulate the cooking temperature. He found a greatly discounted module that set him back just over $30. It even has a self-learning feature that sounds like it’s handy (not sure if all of these have that though).

Check out the video after the break. We like the use of his old RAM heat sinks to help dissipate heat from the solid state relay that drives the heating element. Since that SSR is inside of the foam box we could see heat becoming an issue. This way it’s dissipated, but not wasted.

We’re not going to question the logic that went into putting racing stripes on a slow cooker, but [Evan]’s sous vide machine is the most professional one we’ve seen.

After [Evan] found a cooking book that went into the physics and chemistry of making a meal, he wanted to make some really good meals. Sous vide spoke out to him and [Evan] committed himself to building an immersion cooker.

After trolling around on the Internet, [Evan] came across a little gem on Make. The Make build was cheap – it was built around an off-the-shelf PID controller and thermocouples. [Evan] though about building his own PID controller, but time is money and he couldn’t beat the commercial version in features.

The enclosure was the most time-consuming part of [Evan]’s build. It’s a 1/8″ sheet of aluminum cut and bent to the correct size. The sharp edges were filed down and joined with epoxy; definitely not the ‘normal’ way of building an enclosure. The color scheme is borrowed from this Renault – French cooking inspired by a French car.

As for [Evan]’s results, he cooked a 5oz filet marinated in garlic, thyme, olive oil, salt and pepper. This dish was flanked with some roasted Yukon Gold potatoes and sautéed broccoli. Our mouth is watering just looking at the picture, so we’re betting [Evan] did an excellent job.

We’ve seen no shortage of temperature controlled immersion cooking devices, called Sous-Vide, around here. But this one probably has the capacity of all of them combined! Flickr user [RogueGormet] isn’t writing about the build, but his Large Form Water Oven build photo set speaks for itself.

We’d wager that the donor vessel is a 16-gallon chest cooler. He cut the lid into two sections, sealing off the insulated cavity with High Density Polyethylene (the stuff those white cutting boards are made out of). This gives him a place to mount the heating element, with a box for the PID controller riding on top. A submersible pump keeps the liquid moving to help regulate the cooking temperature throughout.

What do you put in one of these? Right off the top of our heads we’d think he had something like a pig roast planned. But it could just as easily be a Turkey, or other large hunk of meat. What would you use it for?

Tempted by what sous vide cooking has to offer, but balking at the price for a unitasker, [Lee’s] father in law set out to see if he could rig up his own precision temperature controlled cooking system on the cheap. He immediately hit eBay and shelled out about around $75 to get his hands on a solid state relay, PID controller, and temperature probe.

As you can see above, a crock pot serves as the cooking vessel. We’ve seen this method before, either splicing into the power cord, or providing a single outlet on the controller. This version provides a PID controlled outlet to which the appliance can be plugged in. The other outlet in the socket is always on and powers an aquarium pump that circulates the heated water during the cooking process.

The result works quite well, even though it wasn’t a huge cost savings. There are a few issues with positioning of the temperature probe, but that may be where experience comes into play.

It seems that sous-vide cooking is becoming increasingly popular lately. [Meseta] caught the sous-vide bug and wanted to try his hand at it, though he did not have enough money for a premade sous-vide cooker. After seeing a good handful of lackluster DIY sous-vide rigs online, he decided that he would design and build a sous-vide cooker of his own.

He already had a Forebrain microcontroller at his disposal to use as a PID controller, but what he really needed was a cooking vessel. Rather than use an old crock pot or similar device, he purchased a small personal refrigerator that could be used for cooling or heating. The unit ran off a Peltier cooler that could be switched between modes, making it quite easy for him to control.

In his blog, he discusses the modification from beginning to end, and even shows off the results of his cooking endeavors. He hasn’t posted code as of yet, but he says that he is more than happy to share it with anyone who might be interested in building their own sous-vide cooker.

In search of a perfectly-cooked brisket, [Aaron] recently completed this DIY PID-controlled sous-vide slow cooker. Sous-vide (French for “under vacuum”) is a cooking technique in which foods are typically vacuum-sealed and then cooked in a relatively low temperature water bath for an extended period of time. This is done to minimize temperature gradients throughout the food to ensure even cooking. Precise regulation of the water temperature is the key to ensuring that the results are exactly as desired – when cooking for many hours or days, even a few degrees discrepancy can greatly influence the final product.

A few months ago we featured a similar hack that utilized a simple switching temperature controller spliced into an extension cord. Although probably sufficient for most aspiring “hacker-chefs”, the temperature was not as stable as it could be. The problem is that it takes time for the heat generated in the slow cooker’s heating element to reach the temperature probe (and food) suspended in the water bath. By the time the probe reads the elevated temperature, the element is already too hot and the temperature overshoots the target. One way to mitigate this effect is to circulate the water to minimize temperature gradients, as is done in many of the expensive commercial units. In order to achieve similar results, [Aaron] instead created a PID controller that uses temperature feedback over time to precisely maintain the desired temperature and reduce any deviations resulting from outside disturbances.

The build is covered in detail and looks great in a custom acrylic enclosure. All of the board schematics, enclosure layout files, and source code are available under Creative Commons licensing at the bottom of his blog page. A good deal of time is also spent addressing the actual PID programming and tuning – something that could be useful for many different hacks requiring precise feedback control.

The end result is a professional looking control box and a slow cooker that is able to maintain temperature within 1°F even while using a DS1820 temperature sensor that is only rated as accurate to 0.5°C (0.9°F). From the pictures it looks like [Aaron] has finally achieved brisket bliss! Now the only question remaining is: what is the best setting for reheating left-over pizza?